util: `SuppressedError` should print `error`/`suppressed` properties during inspection

Inizia in lib/internal/util/inspect.js, in formatError(), confrontando la gestione speciale esistente per cause ed errors. Estendi l’ispezione in modo che SuppressedError.error e SuppressedError.suppressed vengano visualizzati ricorsivamente, quindi verifica che util.inspect() e console.log() producano l’output annidato richiesto per gli errori di rilascio delle risorse.

What is the problem this feature will solve?

When a SuppressedError is thrown (e.g. from disposal errors during a using/await using block) and inspected via util.inspect() / console.log(), then the actual underlying errors (error and suppressed properties) are not shown:

class Resource {
  [Symbol.dispose]() {
    throw new Error('error during dispose');
  }
}
function test() {
  using res = new Resource();
  throw new Error('error during execution');
}
test();

Current output (Node v26.8.2):

SuppressedError: An error was suppressed during disposal.
    at test (REPL10:3:3)

Both those errors are essential for debugging.

This has the exact same shape as two problems Node already solved for other "container" errors:

AggregateError.errors was silently swallowed during inspection — fixed in #43646 (tracked in #43645).
Error.cause was silently swallowed during inspection — fixed in #41002 (tracked in #40859).

SuppressedError.error / SuppressedError.suppressed fall into the same category and currently have no equivalent handling in formatError() (lib/internal/util/inspect.js).

What is the feature you are proposing to solve the problem?

Extend formatError() so that, similar to how cause and errors are already special-cased, the non-enumerable error and suppressed properties of a SuppressedError are always included in the inspected output (recursively, since a SuppressedError can itself wrap another SuppressedError when multiple disposals fail).

Desired output, roughly matching what the cause-chain rendering already does:

SuppressedError: An error was suppressed during disposal.
    at test (…)
    ... {
  [error]: Error: error during dispose
      at Resource.[Symbol.dispose] (…)
      ...,
  [suppressed]: Error: error during execution
      at test (…)
      ...
}

What alternatives have you considered?

• Manually logging e.error and e.suppressed in application code — works, but requires every catch block to know it might be dealing with a SuppressedError.
• A userland [util.inspect.custom] patch on SuppressedError.prototype — works.

I believe a better out-of-the-box experience is required, rather than user-land patches. Workarounds shouldn't be necessary for a built-in error type tied to a TC39-standardized language feature